Insurance (Obligations Under Funding Agreements - Liability and Collateral) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Outstanding Funding Agreements To Certain SPEs	$ 39,500	$ 39,900
Funding Agreements Farmer Mac
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Outstanding Funding Agreements To Certain SPEs	2,050	2,375
Invested Assets Pledged As Collateral	2,159	2,450
Federal Home Loan Bank of New York
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank amount of advances by branch for funding agreements	15,750	16,200
Collateral pledged relating to obligations under funding agreements	17,981	18,539
Federal Home Loan Bank of Des Moines
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank amount of advances by branch for funding agreements	0	50
Collateral pledged relating to obligations under funding agreements	$ 0	$ 72

Invested assets pledged as collateral.

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- Definition

Amount of funding agreements outstanding to certain SPEs that have issued debt securities for which payment of interest and principal is secured by such funding agreements.

+ References

No definition available.

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- Definition

Amount of advances from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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